When the ceiling of the Treachery room in Richmond Court is moving downwards with Ernest and the Seven Dragons of London trapped within it, Katrielle appears on the other side of the locked door and tries to communicate with the ones inside. Then Inspector Hastings suddenly arrives at the castle, together with some cops. Both he and Katrielle are wondering what the other is doing there. Hastings says that they received an anonymous tip that criminals would be confessing at the castle. Katrielle remembers Ernest that Lord Adamas said the moving ceiling was part of the game and leaves the puzzle to him. Hastings commands his cops to search the castle and capture Lord Adamas. Katrielle and Sherl go back to the boy's room once again.
In the Treachery room, Lord Adamas's voice says that the final game will expose the Seven's true faces and "if they look behind their masks, their crimes will become clear". Mayor Pipper seems to know what to do and asks Hastings to turn around the portraits of the Seven Dragons in the Hope room. Doing so, he finds the message: "When the world turns upside down, perhaps it is a sign. In fact, it will expose your crime. Yet, there's still no atoning your evil designs." Cesar commands Hastings to go to the Twinkling room and turn the painting that is hanging in there upside down. On it, Hastings finds the message: "What's the date?" The Dragons deduce the solution must be September 7th, the date from what happened ten years ago. After typing the code 0907, the ceiling stops moving and the door opens.
Then the voice of Lord Adamas says that for winning the game, he will award them with the dark inheritance that is Richmond's curse. Because the Dragons were able to solve the puzzles, they have shown him proof that they committed the crime from ten years ago and he will have them atone for it by revealing it to the world. Hastings wants the Seven to tell him more about this. Then, one of his cops discovers that Lord Adamas has been playing recordings of his voice via remote control.
Back in the boy's room, Katrielle is inspecting a book when she hears the messages. Then she exclaims to have figured it all out and returns to the hall. Back among the others, Katrielle reveals to know who Lord Adamas is and that he is among them right now.
Lord Adamas turns out to be Ernest. Katrielle became certain of it when she discovered that his voice was pre-recorded. He must have been controlling it with a remote in his pocket. However, the audio was able to deal with Katrielle's participation in Professor Layton's place, so he must already have known that Katrielle would be the one to come to the game. Therefore he must have mentioned Layton's name in the invitation so Katrielle would get stubborn and participate in the game, supporting the Dragons in their attempt to solve the puzzles. And if Katrielle would participate, he would be able to watch it all go down from the front row.
Katrielle directly continues by revealing that Ernest's real name is Miles Richmond and that he actually is the grandson of Lord Maximilian Richmond. Katrielle deduced this because of the book she found in the boy's room: "Ernest Shockleton, Surprise Explorer", written by Richard Greeves. The origin of Ernest's alias.
Miles' objective was to verify the truth behind the events of ten years ago and to take revenge on the Seven Dragons, who were involved in them. The Dragons were the ones who got their hands on the hidden fortune of Lord Richmond. Hastings interrupts Katrielle, mentioning that the legends say there was never a fortune in the first place.
Then Emiliana arrives, directly refuting Hastings. She turns out to have investigated the incident that took place ten years ago and discovered the truth behind the whereabouts of Richmond's fortune. Ten years ago, a reconnaissance squad of seven people, called Team Adamas, visited Mount Rosenberg, after hearing rumors that there were diamonds hidden on the mountain. Their objective was to verify to Lord Richmond whether those rumors were true, for the lord had been met with a financial failure and was threatened with bankrupty. However, the conclusion met was that there were no diamonds on the mountain. Emeliana reveals that if her analysis is correct, there were indeed diamonds on the mountain and Team Adamas took them.
It seems that Miles researched the legend that was born from this disappearance for years and eventually discovered that Team Adamas consisted of the Seven Dragons (expect Liza, for she replaced her deceased father only five years ago). Shocked, he planned and carried out the puzzle game to see if it was true. By threaten them by saying he would reveal their secret, he forcefully made them participate. He then gave a tip to the police, and as the final game, he had the inspector participate in the puzzle-solving, thereby pushing the Dragons to confess once it was all over.
Katrielle is impressed by the detail of Miles' plan but still finds it unfortunate. Miles reveales to be aware of how foolish all of it was, but he had to do it to keep his promise to his mother. When Lord Richmond died, he and his mother were left without any sort of inheritance and lived in poverty. But the day before his grandfather died, he heard him and his mother about the diamonds. For if they had the diamonds, his mother would not have had to suffer, he promised her on her deathbed that if someone stole the diamonds, he would get revenge. That is why he wanted to make the thieves spill the truth from their own mouths. But Katrielle figured everything out before he could make it happen.
Hastings then instructs Miles and the Dragons to come with him to the station. But Katrielle orders them to wait, for she was not disappointed because all of this, but because Miles did not see that Lord Richmond himself made the Dragons do everything that they did. She shows the deed to Mount Rosenberg, whereon Lord Richmond wrote that if gems were ever found on the mountain, he would transfer ownership of the land to the party who discovered it. He did this ahead of time so that the Team members would not be seen as criminals if the diamonds' existence was ever revealed to the world.
Katrielle takes everyone to the roof of the castle, showing them the real Richmond fortune: The city of London. Knowing his death was imminent, Lord Richmond wanted to use the then undiscovered diamonds for the development of London, rather than for himself, so he let the work to the city's most trustworthy people: the Seven Dragons. The Dragons were no thieves, but they were the key influential figures in London who took Lord Richmond's dream.
The Dragons apologize Miles foor keeping quiet until now, but they could not tell him about it when he was younger for that was what his mother wanted. it seems that when the lord was nearing his end, he told her everything. Apparently, she did not complain at all about the lord's decision not leaving her an inheritance. She chose not to tell Miles about it for she was worries about whether he would be able to make it on his own. But when he showed her how determined he was to figure out the truth about the missing diamonds, she did not deny his wish, to give him a focus that would help him grow strong. When the Dragons got their invitations for the puzzle game, they realized it might been Miles who would be running the show. They participated because they wanted to see if he knew the truth. They believed in him, even during the final game, for if he was truly from the kind Richmond family, he would not actually take their lives. But they never expected that Miles himself was participating in the game with them.
Miles might have planned to manipulate the Dragons with his plan, but in reality he was guided by his mother, just like them. Realizing this, Miles feels guilt for what he did. But the Dragons ensure him not being in the wrong, for he tried to keep his promise to his mother. By living as Ernest Greeves, he learned kindness and the importance of friendship and became a lovely person; something his mother would be more proud of than anything else.
Katrielle asks Hastings if he is still going to arrest Miles, upon which he says that if this accident has no victims, then he has no reason to. Emiliana confesses that this time, she will have to acknowledge Katrielles ability.
Back at the Detective Agency, Miles is about to say the place farewell. But when Katrielle arrives, she is still able to consider him as her assistent Ernest and asks him to prepare some tea for her for it is going to be a busy day.
- Katrielle Layton
- Ernest Greeves / Miles Richmond
- Madame Gretchin Doublée
- Mayor Pipper Lowonida
- Phineas T. Barnone
- Liza Wight
- Grant Sloanes
- Cesar Chance
- Mustafa Fullhold
- Inspector Ercule Hastings
- Emiliana Perfetti
- Lord Maximilian Richmond (flashback)
- Miles' mother (flashback)
- Liza's father (flashback)
- Kat's failure to solve the puzzle*
- The Seven Dragon's past*
- Maximilian Richmond and the Dragons' relationship*
- The deed to a mountain*
- The voice is a recording
(The clues marked with a * appear in the former episode.)
- Katrielle compares this episode's case to baumkuchen: "It was built slowly, layer by layer, over a long period of time."